docs: async def set_avatar(self, url: str):
          """
          Set the avatar of the user. See also: `API reference`_
  
          Args:
              url: The new avatar URL for the user. Must be a MXC URI.
  
          .. _API reference:
             https://matrix.org/docs/spec/client_server/r0.3.0.html#put-matrix-client-r0-profile-userid-avatar-url
          """
          await self.ensure_registered()
          content = {"avatar_url": url}
          await self.client.request("PUT", f"/profile/{self.mxid}/avatar_url", content)